Process of building fibrous sheets



April 3, 1934. c. A. BAER PROCESS OF BUILDING- FIBROUS SHEETS Filed MaylO, 193,2

Patented` Apr. 3, 1934 UNITED STATES 4PATENT oFFlcE 12 Claims.

This invention relates to a process of manufacturing fibrous sheets anda product produced by the practice of such process.

An object of the invention is to provide a strong, flexible andinexpensive material capable of being employed as a substitute for wovenfabric or other similar material.

Another object of the invention is to provide a simple and practicablemethod of forming fibrous material into strong and flexible sheetswithout the necessity for spinning, weaving, knitting or any of thenumerous manufacturing processes now required to accomplish this resultto obtain an equivalent article, after the usual steps of textilepreparations are completed.

Another object of the invention is to dispense with the spinningoperation now ordinarily involved in the manufacture of textilematerials by employing a resilient bonding agent for holding togetherthe fibers coming from machines employed for cleansing vand arrangingthem in any desired order.

Another object of the invention is to provide a single and continuousprocess for converting loose fibers into a continuous strand or sheet byfirst arranging them in the desired order and then applying a bondingagent thereto which Will hold the fibers permanently in interlockingrelation.

Another object of the invention is to form loose l and unfabricatedfibers into a finished product by an additional step in the process oftextile preparation.

Another object of the invention is to provide a process by which certainfibrous materials having very smooth exterior surfaces can be fabricatedto form relatively strong material whereas if the tenacity of the fibersalone were relied upon the product would have a much lower tensilestrength. y

Another object of the invention is to fabricate the loosely arrangedfibers delivered in sheet form by a carding or other similar machineinto a product having great longitudinal tensile strength and asufficiently high transverse tensile strength to be suitable for formingthe plies employed in the construction of pneumatic tires.

Another object of the invention is to provide a relatively strong fabriccomposed of a mixture of cotton and asbestos fibers and formed directlyinto fabricated sheets from a mixture of the loose fibers of suchmaterials.

The invention generally contemplates the collection of loose fibers inany desired form, as for example in a continuous sheet, and thenemersing or otherwise impregnating them with a latex solution capable ofcoagulation upon the fibers to hold them permanently together to form astrong, fabricated material. In the illustrated embodiment of theinvention the fibers are delivered upon a moving conveyor from cardingor other suitable fiber arranging machines, where the fibrous webs orsheets thus delivered are superposed one upon another to ,form acomposite fibrous sheet. Such composite sheet is discharged from the endof the conveyor into a'tank containing a solution of latex or othersimilar substance which binds the iibers together in whatever relationthey are in when the bonding agent coagulates. A dryer or heater vof anysuitable character may be employed to assist in coagulating the bondingagent. While any kind of fibers may be employed in broadly practicingthe process, as a matter of illustration in the present instance thefibers will be considered as being of an asbestos and cotton mixturecapable of forming a sheet of material the tensile strength of which isnot so injuriouslyvaliected by the high operating temperaturesencountered in fabrics employed in the manufacture of pneumatic tires,

as fabrics now conventionally used for this pur- In the drawing:

Fig. 1 is a diagrammatical plan view of an apparatus which may beemployed for practicing the process herein disclosed and with thefabrlcated fibrous sheet resulting from the practicev of the productillustrated therein.

Fig. 2 is a longitudinal sectional view through the apparatus andproduct illustrated by Fig. 1.

Fig. 3 is a view illustrating a slightly different 90 form of apparatusfor practicing the process embracing the principles of the invention.

. Referring particularly to the drawing there is employed in practicingthe invention one or more carding or other machines such as 10, 11 and12, 95

'adapted to form and to deliver one or more fibrous sheets or webs 13,14 and 16 respectively. These sheets as delivered from the cardingmachines consist of loose and independent fibers arranged in any desiredorder depending upon the `manner in which they are treated within the Inthe present instance cotton and machines. asbestos fibers in any desiredproportion are uniformly distributed upon supporting surfaces within themachines with the fibers lying generally in parallel relationlongitudinally of the sheets but preferably overlapping one another toan appreciable extent. These are discharged over angularly disposedglass bars 17, or other suitable devices, upon a continuously movingconveyor 18 supported at the opposite ends thereof on rollers 19 and 21.Shafts 22 and 23 extending through the rollers for supporting the latterare rotatably mounted in bearings 24 and the shaft 23 is driven in anysuitable manner as by a driving shaft 26 and gears 27.

The sheets 13, 14 and 16 are superposed upon the conveyor to provide acomposite sheet 28 which is discharged beyond the end of the conveyor 18into a tank 29 containing a solution 31 of latex having therein all theingredients necessary for its coagulation, or any other solutionsuitable for providing a bonding agent between the fibers of thecomposite sheet. 'Ihe tank 29 preferably has stirring or agitatingdevices 32 and 33 projecting therein for circulating the solutioncontained therein to prevent the separation of its ingredients wheresuch is likely to occur. The solution is kept at a. proper consistencyby adding thereto in proper proportions the ingredients adhering to thesheet in its passage therethrough.

In order to hold the composite sheet in a uniform position within thetank there is provided a roller 34 engaging the upper surface thereofand rotatably mounted below the level of the solution 31 therein upon ashaft 36 journaled in the sides of the tank. Fromthe tank 29 the sheet28 is withdrawn through a resiliently mounted pair of pressing rollers3'7 which are adapted to squeeze out of the sheets any surplus liquidadhering thereto. Just beyond the tank a shaft 39 is rotatably mountedin bearings 38 and on which is supported a spreading roller 4l, theexterior surface of which is spirally corrugated in opposite directionsfrom the center thereof. The shaft 39 of the roller 4l is driven fromthe drive shaft 26 through gears 42 in such manner that lthe peripheralspeed of the spreading roller is somewhat greater than the rate ofmovement of the composite sheet 28 thereacross. Under such circumstancesthe spirally formed surface of theV roller tends to pull the edge's ofthe sheet in pposite directions and consequently to remove from thesheet any wrinkles or contraction therein.

Beyond this roller the sheet is passed through any suitable heater ordrier indicated at 43 where the rate of coagulation of the ingredientsof the solution, or the drying of the liquid, is materially accelerated.Beyond the heater 43 the sheet is spirally wound in the form of a roll44 upon a shaft 46 which is driven by frictional contact between theexterior surface of the roll 44 and a roller 47 in turn driven from theshaft 26 through gears 48.

In addition to the roller 34 for holding the composite sheet 28 inauniform position within the Vtank 29, the sheet also may be held inposition in such region by upper and lower endless belts 52 and 59respectively, and which are preferably of the samewidth as the conveyorbelt 18. These belts may be formed of any material as, for example,rubber or other felting material or of wires or screen suitably arrangedfor this purpose. For positively driving the composite sheet through thetank 29, the roller 34 may be driven by bevel gears indicated at 64 andthis roller may be employed for driving the belt 52 by reason of itsfrictional engagement therewith. Rollers 53 and 54 mounted in the sidesof the tank 29 are employed for holding the belt 52 in engagement withthe composite sheet 29 in the region where the composite sheet entersand leaves the liquid contained within the tank. The upper portion ofthe belt 52 may be housed within a cleaner and drier 51 which may beadditionally employed, if desired, for scrubbing or scraping thecoagulated latex solution from the belt and for returning it to thecomposite fibrous sheet in a clean and dry condition. The lower belt 59is mounted for operation in any suitable manner within the tank as, forexample, upon end rollers 57 and 6l rotatably mounted within the tankand an intermediate pair of rollers 58 mounted in the tank beneath theroller 34. Either one or both of the rollers 5'7 and 61 may be driven inany suitable manner as, for example, by a chain and sprocket mechanism66 driven from the shaft 23. Either or both of the pressing rollers 37may be driven by a chain and sprocket mechanism 63 driven by the sameshaft also may be employed for driving any numberof the rollers 68employed in the heater or drier 43 for supporting the composite sheettherein. It is to be understood, of course, that the abovedescribedlmechanism is merely i1- lustrative of the principles of theinvention and that any other suitable mechanism may be employed forconveying the fibrous material during the various steps in practice ofthe process to which the invention principally relates.

The coagulated latex upon the sheet forming the roll 44 tends tocondense the bers into a relatively compact form wherein they adhere toone another tenaciously by reason of the irregular formation thereof andthe coagulated substance thereon.

In this form the sheet constitutes a finished produce which may beemployed for whatever purpose desired, an illustration of one use ofwhich is in the formation of plies for pneumatic tire construction. Whenso employed it is apparent that the material will have great strength ina direction parallel to the fibers and by reason of the interlockingrelation of the fibers will be considerably stronger in a directionperpendicular to the fibers than materials now employed.

The asbestos bers when employed will not be appreciably affected by thetemperatures encountered in the operation of pneumatic tires andconsequently will not deteriorate in tensile strength at such a rapidrate as do the cotton fibers now employed.

It is to be understood that any kind of fibers may be employed inconstructing a fabric embracing the principles of this invention andthat any kind of machine for arranging the fibers in the order desiredlikewise may be employed.

In Fig. 3 there is disclosed an apparatus by which a solution of latexwith suitable ingredients therein may be sprayed or otherwise depositedupon the sheets either separately or in composite form as such sheetsare delivered upon the conveyor 18 from the carding machines, one ofwhich is indicated by the numeral 10. Any suitable spraying ordepositing device such as-a perforated pipe indicated at 49 may beemployed for this purpose. The fibrous sheets so'impregnated with thesolution may be heated or dried as hereinbefore described to increasethe rate of coagulation of the solution and then may be 'wound in rollsfor shipment.

While the process and product herein disclosed constitutes a preferredform and application of the invention, it should be understood thatthere are numerous modified and equivalent ways of practicing theprinciples of the invention within the scope of the appended claims.

I claim:-

1. The process of fabricating fibrous materials which comprisesassembling loose and independent dry fibres into a composite homogeneoussheet comprised of multiple film-like layers of undrawn carded fibreswith the fibres in each film longitudinally arranged and in naturaltension and subsequently to the formation of the homogeneous multiplefilm-like fibre sheet, applying to said sheet abonding agent for holdingthe fibres together to form a compressed and interlocking mass, andallowing the bonding agent to set with the fibres maintained in theirnormal lengthwise position and under normal tension during bonding andsubsequent settingof the bonding agent.

2. The method of forming fabricated sheets which comprises uniformlydistributing" loose and independent dry flbres upon a supporting surfaceto form a web of overlapping fibres which comprises a plurality ofcarded fibrous films superimposed upon each other with the fibres ineach film longitudinally arranged and in natural tension and while theweb of fibres is carried by the supporting surface and thereaftersubsequently to the complete formation of the web of multiple films uponsaid surface impregnating said web with a coagulative bonding agent toprovide a composite fabric.

3. The method of forming fabricated lfibrous sheets 'which comprisesuniformly distributing loose and independent dry fibres upon a movablesupporting surface to form a web of overlapping fibres comprised of aplurality of carded fibrous films superimposed upon each other with thefibres in each film longitudinally arranged and in natural tension, and`while the web of fibres is carried by the supporting surface andsubsequently to the complete formation of the web of multiple films uponthe movable surface impregnating the fibrous structure with acoagulative bonding agent to provide an interlocking fibrous mass.

4. 'I'he method of forming loose and independent dry fibres into acomposite product which comprises arranging said fibres under naturaltension in overlapping relation and in a plurality of superimposedcarded films with the fibres in each film longitudinally arranged upon asupporting surface and in thereafter applying a coagulative bondingagent to said fibres, compressing said flbres together to expel theexcess bonding agent and to assemble the fibres in more compact relationand thereafter with the fibres left in their previously arrangedlengthwise position heating said product to increase the rate ofcoagulation of said bonding agent.

5. The process of forming a fabricated product which comprises uniformlydistributing loose and independent dry fibres upon a supporting surfaceto form a web of overlapping fibres comprised of a plurality of cardedfibrous films superimposed upon each other with the fibres of each filmlongitudinally arranged and in natural tension and subsequently to thecomplete formation of the web of multiple films upon the supportingsurface applying a coagulative bonding agent to said fibres, thereaftercompressing said fibres to eliminate the excess bonding agent therefromand to assemble the fibres in more compact and interlocking relation,and then effecting setting of the product while the fibres remain intheir previously arranged lengthwise position and in their subsequentlycompacted condition.

6. A process of forming a fabricated fibrous product which comprisesuniformly ldistribut ing loose and independent dry fibres upon asupporting surface to form a web of overlapping fibres comprised of aplurality of carded fibrous films superimposed upon each other with thefibres in eachl film longitudinally arranged and in natural tension andsubsequently to the ycomplete formation ofthe web of multiple films andwhile said web is supported upon the surface immersing the web in alatex solution conanother to provide a continuous composite.

homogeneous sheet, thereafter after the complete formation of thefibrous sheet immersing said composite sheet in a coagulative latexsolution, and in effecting setting of the latex solution with the fibreslunder natural tension no greater than normal carding tension.

8. The method of forming fabricated sheets which comprises successivelysuperposing dry carded fibrous laps upon a continuously moving bresupporting conveyor, with the fibres in each lap longitudinally arrangedwith respect to each other and under natural tension, and thereaftersubsequently to the superposition of the fibrous laps impregnating saidlaps with a coagulative solution providing a bonding agent betweenfibrous elements thereof, and in effecting settingy of the bonding agentwhile the fibrous elements of the laps are maintained under no greaterlengthwise tension than that of the lengthwise tension of the fibrouselements'of the laps upon impregnation with the bonding agent.V

9. A fabricated product comprising a carded but undrawn fibrous webhaving the fibrous thereof secured together by a coagulative bondingagent with the fibres secured together under no greater lengthwisetension than the lengthwise carding tension of the fibres and with thefibres arranged lengthwise of the web and generally parallel with oneanother and in relatively straight condition.

10. A fabricated product comprising a plurality of fibrous sheets ofundrawn carded fibres secured together by a coagulative bonding agentwith the fibrous sheets under natural tension and with the fibresarranged lengthwise of the web and generally parallel to each other,relatively straight and longitudinally arranged in the sheet.

11. The invention set forth in claim l0 in which the fibres comprisecarded asbestos fibres'.

12. The invention set forth in claim 10 in which the fibres comprisecarded cotton and asbestos fibres.

CARL A. BAER.

